Establishing and maintaining means for siphon connection between liquid storage tanks



Feb. 4, 1958 J. J, PACEY ErAL 2,821,993

ESTABLISHING AND MAINTAINING MEANS FOR SIPHN CONNECTION BETWEEN LIQUID STORAGE TANKS Filed Aug. 8, 1956 2 Sheets-Sheet 2 ATTORNEYS Feb. 4, 1958 J. J. PACEY ETAL 2,821,993

ESTABLISHING AND MAINTAINI'NG MEANS FOR SIPHON CONNECTION v BETWEEN LIQUID STORAGE TANKS Filed Aug. 8, 1956 2 Sheets-Sheet 1 `.ICal-1N J- PACEY' GEORGE D- ROBINSON,JR

BY 14M. 'f ATTORNEYS United States Patent ,John J. Pacey, Springfield, `and George D. Robinson, Jr.,

Agawam, Mass., assignors to Gilbert & Barker Manufacturing Company, West Springfield, Mass.l,.a corporation of Massachusetts ApplicationjAugust 8, 1956, Serial`N0..602,851

1 Claim. ,(Cl.'137,144)

This invention relates to improvements in `liquid disijpensing systems of the kind wherein two storage tanks are interconnected by a'siphon and :a pumpfsubmerged in one tank forces liquid underV pressure Vto one yor more .dispensing locations.

The invention, while not limited thereto, `has one advantageous use in connection with the dispensing of `gasoline at service stations.

The invention has for one lobject the provision of means, voperable automatically whenever the pump l.is started, to `render the siphon eiective in lthe event that .it lis not already so.

Another object of theinventionis to provide means for by`passing a small part .of `the pumped liquid through an ejector to create suction which is applied to the Siphon to rid it of any air that may ybe ,present therein.

A further object of the invention is to also utilize the by-pass for the elimination of air from the liquid before the outlet valve for liquid can be opened, whereby airfree liquid only can pass to the dispenser.

These and other objects will more particularly appear from the following description of one preferred embodiment of the invention in the accompanying drawings, in which,

Fig. l is a small scale diagrammatical View of a liquid dispensing system embodying the invention;

Fig. 2 is a sectional elevational view of the tank, motor-driven pump and the valve housing containing the ejector; and

Fig. 3 is a sectional View of the housing drawn to a larger scale and showing the suction connection of the ejector and its valve means.

Referring to these drawings and rst to Fig. l thereof, the invention is adapted for use in connection with la gasoline dispensing system having a plurality of supply tanks, such as 1 and 2, which are interconnected by a siphon pipe 3 so that tank 1 will feed tank 2 as gasoline is withdrawn from the latter and the gasoline in each tank will be maintained at the same level. These tanks are usually buried in the ground and disposed at about the same level. Tanks 1 and 2 have the usual fill pipes 4 and 5 and the usual vent pipes 6 and 7, respectively, which latter as shown connect with a riser 8 which may extend upwardly along one wall of the service station, shown in part at 9, and which is provided with a suitable outlet to the atmosphere. Located in tank 2 is an electric-motor-driven centrifugal pump contained within a cylindrical casing 10, which has an inlet 11 near the bottom of the tank and which forces gasoline through an outlet pipe 12 into a housing 13 and thence through one or more outlet pipes 14 to one or more dispensers 15 of any suitable form for metering the gasoline dispensed to the customer and indicating the amount dispensed. The housing 13 is usually located in a pit, such as 16, having a removable cover 17. In this pit also is a junction box 18, through which the supply wires for the motor pass from a conduit 19 to a conduit 20, which extends to a control box 21 located in the service station.

,ICC

:conduit 22 :connects :the control: box to the .dispensers 11,5 and suitable connections .aremade 1so.that the:.punjlp motor .may be started and stoppedfrom any one of .zthe dispensers 15 in the usualorany. suitable manner.

'Referring next to Fig. 2, it will be seenthat the housing .13 is supported .by a mbularstandard 23 from tank. 2. Such l,standard has threaded on` opposite ends upper.` and .lower `anges 24 and25, respectively. Flange 25. is

welded to tank .2. Flange 24.is bolted to aange 26 on the housing 13. .The pump outlet ypipe 12 ,is of less diameter than pipe 23 leaving .betweenthem a .passage 27. `The vupper end of pipe .12 is threaded `into the bottom wall 2.8- of housing 13. ,The .conduit 19 passes into the housing .13 through :a .stufling box 29 .andpdownv-wardly 4through outlet pipe 12 into .the casing of the pump-motor. A passage 30 isleft .between conduit 19 and-pipe 12 for :the passage of liquid -fromthe pump into the interior of housing 13. `The latter is subdivided by a partition 31 vrinto inlet and outlet chambers r32 and 33 .respectively `The-discharge pipes 14 are connected to the .outlet chamber 33. In the partitionl31, is a check valve 34 which ,opens upwardly under the. pressure ofthe pumped .liquid and closes by gravity'when .the pump stops. Astop 35 on the bottom ofthe closure cap` 3.6 for chamber 33 limits the .extent of upward movement gasoline.

The motor-driven centrifugal pump may be of any suitable type and the type herein shown as an illustrative example, is constructed as disclosed in the copending application of Harry F. Tapp, filed June 28, 1956 under Serial No. 594,517. The pump 39 is mounted in the lower part of casing 10. The motor is located above the pump 39 and comprises a stator 40, rotor 41, driving shaft 42 connected to the several pump impellers, and upper and lower end bells 43 and 44, respectively. The casing of the motor, which in this case comprises the stator 40, is less in externalv diameter than the internal diameter of casing 10 leaving a passage 45 which connects the outlet of the pump to outlet pipe 12. Conduit 19 connects with the upper end bell 43. The casing 10 is less in external diameter than the internal diameter of standard 23.

This invention is directed to automatically making the Siphon 3 operative initially and maintaining it operative thereafter. To this end, a portion of the liquid forced upwardly by pump 39 is by-passed through au ejector and the suction developed by the latter is applied to the siphon 3. This ejector is formed by a member 46, threaded into the upper end of a vertical passage 47 formed in one wall of the inlet chamber 32. The member 46 has a head 48 on its upper end and its lower end 49 is frusto conical shape and radially spaced slightly from a similarly shaped part of the passage 47. The spacing between these frusto conical parts is limited by the abutment of head 48 with the top of the wall into which member 46 is threaded. A plug 50 in a portion of the wall of chamber 32 that overlies head 48 enables the assembly or removal of member 46. The member 46 has an axial passage 51 therethrough disposed coaxially of passage 47. The latter opens into the annular space 27 between pipe 12 and the tubular standard 23. A side inlet 52 for the ejector is formed in the last-named wall and opens at its inner end into the space between the adjacent frusto conical portions. At its other end, inlet 52 communicates with one end of a passage 53 in a member 54 which is threaded into the last-named wall. The other end of passage 53 is connected by a pipe 55 to the Siphon pipe 3. Passage 53 has intermediate its ends a seat which is engageable by a check valve 56. The latter is yieldingly urged to its seat by a spring 57 acting against a washer 58 that is held in place by a snap ring 59. l

The pump 39, when put in operation forces gasoline upwardly through pipe 12- into inlet chamber 32 and the check valve 34 will be lifted from its seat allowing gasoline to pass into outlet chamber 33 and' thence through one or more discharge pipes 14 to one or more gasoline dispensers 15 all inthe usual and well known way. However, part of the gasoline raised by the pump will be forced into and through the ejector passage 51 into passage 47 and thence through passage 27 back into the upper part of tank 2. The rush of liquid through the passage 51 creates suction in the side inlet 52, opening check valve 56 so that the suction vwill be applied through pipe 55 to the Siphon pipe 3. Assuming that this pipe is lled with air, as it initially would be, this air will be exhausted from the Siphon 3 and forced back into the upper part of tank 2 by way of passages 47 and 27. Normally, the siphon will not be filled with air but it frequently happens that air enters it through leaks and thus destroys its effectiveness. Any such air will, of course, be removed automatically by the ejector whenever pump 39 is started. Air entraned with the gasoline may also accumulate in the Siphon 3 and be removed in the same manner. So, also if the gasoline in tanks 1 and 2 falls below the lower ends of the pipe 3 and breaks the Siphon, the latter will be again reestablished when the pump is started. Thus, the invention automatically maintains the Siphon effective.

As soon as pumping ceases, check valves 34 and 56 close and the inlet chamber 32 and pipe 12 will drain back into the upper portion of tank 2 which is vented to lwithV air.

the atmosphere and this chamber and pipe become filled The closing of check valve 56 prevents air from entering the Siphon 3. On a subsequent starting of pump 39, the air is forced out through ejector passage 51 and passages 47 and 27 into tank 2. Until this air is eliminated, the check valve 34 will not open. Thus, when andonly when the inlet chamber is filled with airfree liquid does the check valve 34 open. Hence, no air separator is required yat the dispenser. l

The invention thus provides an effective means for automatically maintaining the siphon between two storage tanks in operative condition.l

What is claimed is:

In liquid dispensing apparatus, of the type wherein two storage tanks are interconnected by a Siphon for the flow of liquid from one to another, a pump adapted to have its inlet submerged `in the liquid in one tank, an outlet pipe connected at one end to the outlet of the pump, a housing having an inlet chamber connected to the other end of said pipe and an outlet chamber, said chambers being interconnected by a passage, an outwardly opening valve normally closing said passage, said inlet chamber having a section above and offset from the inlet to said valve passage and constituting the highest portion of said inlet chamber, a by-pass connected at its inlet end to the inlet chamber and having the opening thereto located at said highest portion, said by-pass being adapted for connection at its other end to the upper portion of one of said tanks, an ejector interposed in said by-pass and receiving therethrough part of the pumped liquid, said ejector having a suction passage adapted for connection to the siphon.

No references cited. 

